Roof construction



June 28, 1938. H. w. DAVEY ROOF CONSTRUCTION 3 Sheets-Sheet 1 Filed Jan. 18, 1957 I I 3mm Herbert WDCLVQY June 28, 1938. H, w, DAVEY 2,121,789

RooF coNsTRucnoN 5 Sheets-Sheet 2 Filed Jan. 18, 1957 gww - Herbal-15' WDavg June 28; 193 H 'w DAVEY 2,121,789

ROOF CONSTRUCTION Filed Jan. 18, 1937 5 Sheets-Sheet 5 'Herbert WDaVgy Patented June. 28, 1938 I UNITED STATES PATENT OFFICE 4 Claims.

(Granted under the act of March 3, 1883,35

amended April 30, 1928;. 370 0. G. 757) This invention relates to roofs and it has particular relation to roofs of the promenade tile type I One of the objects of the invention is the pro- 'vision of a roof of the character described which is of sectional construction to form lines of cleavage for permitting the individual sections to expand and contract with changes in temperature without subjecting the entire roof area and walls to the destructive eifect of an accumulated strain.

, Another object of the invention is theprovision of a roof comprising a substructure and a superr structure with a plurality of channels located therebetween for conducting moisture, that may penetrate the superstructure, toward the gutters and drainage outlets at the edges of the roof. -A further object of the invention is the pro-' vision of a roof embodying certain materials and 20 the arrangement and treatment thereof such as will render the structure practically leakproof.

-With these and other objects in view, as well as other advantages that may be incident to the use of the improvements, the invention consists in the 25 parts and combinations thereof hereinafter set forth and claimed, and with the understanding that the several necessary elements constituting the same may be varied in proportion and arrangement without departing from the "nature and scope of the invention, as defined in the appended claims.

In order to make the invention more clearly understood, there are shown in the accompanying drawings, means for carrying the invention into 35 practical use, without limiting the improvements in their useful application to the particular construction, which, for the purpose of explanation, have been made the subject of illustration. In the accompanying drawings: 40 Fig. 1 is a fragmentary perspective view with portions broken away of a roof constructed in accordance with the invention:

Fig. 2 is a similar viewshowing the parapet ,wall and a drainage outlet;

, of drainage outlet;

Fig. 4 is a fragmentary vertical sectional view of the roof structure;

50 Fig. 5 is a vertical sectional view taken on line" Fig. 3 is a similar view showing another form 8 is a vertical sectional view taken on line 88 of Fig. '7',

Referring to the drawings, the improved roof preferably comprisesa reenforced concrete substructure l0 which is supported by the parapet 5. walls".

The surface of this substructure being flat, is first graded by applying a layer I 2 of cement, sand and slag, preferably in the proportion of one, three and six, respectively, which is sloped to 10 approximately one-quarter of an inch to the foot of run toward the drainage outlet of the roof hereinafter to be described. This layer I2 is laid'to the desired grade and divided by suitableretainers or forms into rectangular units 13 (Fig. 1) of approximately six feet, one inch by six feet, sevenand one-half inches, or an area corresponding to that built from the size of the particular tile employed, which, inthe present instance, measures eight nine-inch tiles for the width of the unityby thirteen six-inch tiles for the length, inclusive of the compressible material interposed between the tiles. -The space occupied by the retaining strips or forms during the construction of the units I3 is filled with a compressible road joint material l4 so as to form expansion joints, the same being substantially one-half inch thick and filling the spaces for the full depth of the units l3. The layer 12 is then coated to a depth of approximately one inch with a two-to-one mixture of-sand and cement so as to provide a finished lower subdrainage surface l5. The material of the expansion joints l4 preferably extends to the upper plane of the subdrainage surface I 5 so as to insure complete cleavage between the several units l3.

Over this entire surface, including the expansion joints I4, is next laid a ten-ply impregnated roofing felt l6 which is thoroughly mopped with a waterproofing material such as asphalt. at a temperature not exceeding 450 F. or less than 350 F. so as to provide a smooth surface covering all expansionjoints, the location of which must be unmistakably known by suitable mark- ;ings such as chalk lines or the like made onparapet walls. The waterproofing 'material, should extend to all outer edges of the roof and continue up the parapet walls II to thepoint where the counterflashing I8 is secured.

Over the entire waterproofed surface above described, a plurality of inverted channel members l8 arelaid in parallel relation-and spaced apart approximately sixteen inches from center to center, certain of the channel members being centered over the longitudinal and transverse expansion joints l4 in the units l3 therebeneath. The members l9 are preferably one inch deep and three inches wide, the top surfaces of the members being provided with one-half inch holes 20 spaced apart about four inches, center to center. I

After the channel'members l9 are positioned laterally and longitudinally, as shown in Figs. 2 and 3, a two-to fione mixture of sand and cement 2| is laid therebetween to .a depth corresponding to the depth of the members and leveled to provide a smooth upper subdrainage surface. Strips 22 of non-impregnated felt are next laid over the channel mem er IE to prevent structural material from entering the holes 20 during the succeeding operations. Concrete blocks 23 of gravel concrete, one to two and onehalf to five and about three inches thick, and provided with metallic marginal bands 24, are

next laid overthe concrete 2!! and channel members l9. Theareas of these blocks 23 are equal to those of the units l3 but are not suflicient to overlap the expansion joints l4 in the subroof covering beneath these 'blocks.

This entire concrete area is then givena thorough coating 25 of hot asphalt which is preferably applied at temperatures between 350 F. and 450 F., so as to provide a smooth surface upon which cold process clay emulsified asphalt 26 is next applied in a layer of about threeeighths of, an inch thick and combed to provide a serrated surface. Upon this prepared adhesive surface the promenade tile 21 is laid, between each of which a strip 28 of three-ply rubberoid felt is positioned. Aspreviously explained, the tile should not overlap the expansion joints in the units I3 and preferably are ofsix inches by nine inches in dimensions. Only suflicient asphalt should be applied at onetime as may be found, under existing atmospheric conditions, to remain adhesive. Hot asphalt joint material 29 is next poured around and between the tile to a depth slightly less than the thickness of the tile.

The outer edges of the roof surface and the parapet walls I I, as well as the areas set aside for gutters and scuppers 30, are lined with hot rolled copper sheeting 3| in shapes consistent with theneeds of the work.

Thecounterfiashings ill of cold rolled copper sheeting formed into the necessary shapes are held in position by copper straps 32 attached about twenty-four inches apart to the flashing 3i, and are secured to the parapetwall by lead wedges asindicated at 33. The joint at this point is sealed against moisture by a bitumastic material thoroughly pressed into the wall before the counterilashing is secured in position. .Packs 34 of cold asphaltic road joint material are positioned between all structural materials and flashings for the full depth of the work to form pressure cushions to accommodate expansion.

Between all galvanized drainage pipes and copper outlet boxes 35, and all places where galvanized metal and 'copper come in contact, a three-ply layer of water-proof material 36 is laid,

When roof surfaces are so designed that large areas are perpendicular to one another, as shown in Fig; 7, a specially designed juncture is employed to permit greater flexibility, and avoid rupture.

The valleys 39 formed at these junctures arefilled to the'elevation of the upper surface of the. subdrainage 2|, with a mixture MI consisting of blue-stone and a bituminous binder, and the space between expansion joint material is also filled to a level immediately below the surface tile ,21 with relatively narrow concrete. blocks ll.

provided (Fig.6) In this construction the upper or surface bell trap fits loosely into the lower bell' trap, so that both surface and subsurface drainage may be conveyed through the same drain pipes.

The salient points of departure from the previous constructions of promenade tile roofs'reside in thecorrect placing of expansion joints in the most'geffective locations; of establishing subdrainag'e surfaces and channels for conveying to the subdrains all moisture that may pass below the roof surface; and in the roof surface the establishment 'of flexible material sufficient to prevent the destruction of the whole through the accumulative expansion and contraction of each individual tile composing the roofs surface. The combined application of all these materials in a manner peculiar to the design herein described will result in completely eliminating destructive movement over large areas of roofs which naturally expand under rising atmospheric. 7

cases where waterproof felts are required to adhere to copper surfaces, the faces of these This has been found to be a very positive means of securing a bond between these elements. All parts of this roof are held in place by adhesion and gravity, as shown in the accompanying drawings.

The invention herein described may be modifled in construction and arrangement of the parts by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

The invention disclosed herein may be nianu- V factured and used by'or for the Government of Y the United States without the payment of any royalty thereon or therefor. I claim:

1. A roof comprising a substructure supported by the walls of a building, a superstructure sup- .ported by said substructure and including a plurality of sections separated by expansion joints, a plurality of blocks, one supported by each of said sections and also separated by expansion joints coinciding vertically with said first mentioned expansion joints, and a tile covering for each block, the tiles adjacent to the edges of each block being separated from the corresponding tiles of an adjacent block by expansion joints coinciding with said first and second mentioned expansion joints to provide lines of cleavage extending vertically entirely through said superstructure and drainage passageways extending along said lines of cleavage.

2. A roof comprising a monolithic substructure supported by the walls of a building, a superstructure supported by said substructure and including a plurality of concrete sections separated by expansion joints, a pluralityof concrete blocks, one' supported by each of said sections and also separated by expansion joints coinciding vertically with said first mentioned expansion joints,

35 soft copper sheets must be thoroughly defaced.

structure, and

vblock, the tiles I aiamse a tile covering for each block, the tiles adjacent to the edges'of each block being separated e corresponding tiles of an adjacent block by expansion joints coinciding with said first and second mentioned expansion joints to provide lines of cleavage extending verticallyentirely through said superstructure; and channel mem- 1 rs disposed between said sections and said blocks for conveying moisture toward the outer edges oi'the roots 1 3, A roof comprising a substructure supported by the walls of a building, a superstructure supported by said substructure and including a plurallty 0! sections separated by expansion joints,

a plurality of blocks, one supported by each of also separated by expansion said sections and joints coinciding vertically with said first mentioned expansion joints, a tile covering for each adjacent to the edges of each block beingfseparated from the corresponding tiles or an adjacent block byexpansion joints coinciding with saidflrst and second mentioned expansion joints to provide lines of cleavage extending vertically entirely through said superchannel members extending along from said lines of cleavage between said sections and said blocks for conveying moisture penetrating said second and third mentioned expansion joints toward the outer edges of the roof.

4. A roof-comprising a substructure supported tioned expansion joints, a multi-ply waterproofed fibrous roofing material interposed between said section and said blocks, a tile covering for each block, the tiles adjacent to the edges of each block being separated from the corresponding tiles of an adjacent block by expansion joints ,coinciding with said first-and second mentioned expansion joints to provide lines of cleavage extending vertically entirely through said superstructure, and a layer of clay and emulsified asphalt disposed betweensaid blocks and said tiles and in which the latter are laid.

HERBERT W. DAVEY. 

